U.S. patent application number 16/991914 was filed with the patent office on 2021-07-01 for devices and methods including polyacetylenes.
This patent application is currently assigned to PolyJoule, Inc.. The applicant listed for this patent is PolyJoule, Inc.. Invention is credited to Ian W. Hunter, Timothy Manning Swager, Zhengguo Zhu.
Application Number | 20210202187 16/991914 |
Document ID | / |
Family ID | 1000005447985 |
Filed Date | 2021-07-01 |
United States Patent
Application |
20210202187 |
Kind Code |
A1 |
Hunter; Ian W. ; et
al. |
July 1, 2021 |
DEVICES AND METHODS INCLUDING POLYACETYLENES
Abstract
Embodiments described herein relate to compositions, devices,
and methods for storage of energy (e.g., electrical energy). In
some cases, devices including polyacetylene-containing polymers are
provided.
Inventors: |
Hunter; Ian W.; (Cambridge,
MA) ; Swager; Timothy Manning; (Newton, MA) ;
Zhu; Zhengguo; (Chelmsford, MA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
PolyJoule, Inc. |
Cambridge |
MA |
US |
|
|
Assignee: |
PolyJoule, Inc.
Cambridge
MA
|
Family ID: |
1000005447985 |
Appl. No.: |
16/991914 |
Filed: |
August 12, 2020 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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15793737 |
Oct 25, 2017 |
10777368 |
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16991914 |
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13799152 |
Mar 13, 2013 |
9831044 |
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15793737 |
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61623887 |
Apr 13, 2012 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H01G 11/48 20130101;
Y02E 60/13 20130101; H01G 11/32 20130101; Y02T 10/70 20130101; H01G
11/38 20130101 |
International
Class: |
H01G 11/38 20060101
H01G011/38; H01G 11/32 20060101 H01G011/32; H01G 11/48 20060101
H01G011/48 |
Claims
1. An electrical energy storage device, comprising: a first
electrode comprising a polymer comprising a substituted or
unsubstituted polyacetylene; a second electrode in electrochemical
communication with the first electrode; a porous separator material
arranged between the first and second electrodes; and an
electrolyte in electrochemical communication with the first and
second electrodes.
2. An electrical energy storage device as in claim 1, wherein the
electrolyte is a substantially free of metal-containing
species.
3. An electrical energy storage device as in claim 1, wherein the
polymer comprising the substituted or unsubstituted polyacetylene
is synthesized in the presence of a fluid carrier.
4-5. (canceled)
6. An electrical energy storage device as in claim 1, wherein the
electrolyte is a substantially free of lithium-containing species
or lithium ion-containing species.
7-8. (canceled)
9. An electrical energy storage device as in claim 1, wherein the
electrolyte is an ethylene carbonate solution or a propylene
carbonate solution, the solution comprising a salt having the
formula, [(R).sub.4N.sup.+][X.sup.-], wherein X is
(PF.sub.6).sup.-, (BF.sub.4).sup.-, (SO.sub.3R.sup.a).sup.-,
(R.sup.aSO.sub.2--N--SO.sub.2R.sup.a).sup.-,
CF.sub.3CO.sub.2.sup.-, (CF.sub.3).sub.3CO.sup.-, or
(CF.sub.3).sub.2CHO).sup.-, wherein R is alkyl and R.sup.a is
alkyl, aryl, fluorinated alkyl, or fluorinated aryl.
10. An electrical energy storage device as in claim 1, wherein the
substituted or unsubstituted polyacetylene polymer is arranged as
an n-type material.
11. An electrical energy storage device as in claim 1, wherein the
substituted or unsubstituted polyacetylene polymer is arranged as a
p-type material.
12-20. (canceled)
21. An electrical energy storage device as in claim 1, wherein the
polymer comprises the structure, ##STR00006## wherein: R.sup.1,
R.sup.2, R.sup.3, and R.sup.4 can be the same or different and each
is H, alkyl, heteroalkyl, aryl, heteroaryl, heterocyclyl, halo,
cyano, sulfonyl, sulfate, phosphonyl, phosphate, or carbonyl group,
any of which is optionally substituted; and m and n are each
greater than 1.
22. An electrical energy storage device as in claim 21, wherein
R.sup.1, R.sup.2, R.sup.3, and R.sup.4 are each H.
23. An electrical energy storage device as in claim 21, wherein at
least one of R.sup.1, R.sup.2, R.sup.3, and R.sup.4 is
fluorine.
24. An electrical energy storage device as in claim 1, wherein the
polymer has the structure, ##STR00007## wherein m and n are greater
than 1.
25. An electrical energy storage device as in claim 1, wherein the
polymer has the structure, ##STR00008## wherein: R.sup.1, R.sup.2,
R.sup.3, and R.sup.4 can be the same or different and each is H,
alkyl, aryl, halo, cyano, sulfonyl, sulfate, phosphonyl, phosphate,
or carbonyl group, any of which is optionally substituted; and m,
m', n, and n' are each greater than 1.
26. An electrical energy storage device as in claim 1, wherein the
polymer has the structure, ##STR00009## wherein: R.sup.1, R.sup.2,
R.sup.3, and R.sup.4 can be the same or different and each is H,
alkyl, aryl, halo, cyano, sulfonyl, sulfate, phosphonyl, phosphate,
or carbonyl group, any of which is optionally substituted; and m,
m', n, n', and o are each greater than 1.
27. An electrical energy storage device as in claim 1, wherein n,
n', m, m' and o are the same or different and are an integer
between about 2 and about 10,000, or between about 10 and about
10,000, or between about 100 and about 10,000, or between about 100
and about 1,000 r.
28. An electrical energy storage device as in claim 1, wherein the
polymer has a molecular weight between about 500 and about
1,000,000, or between about 500 and about 100,000, or between about
10,000 and about 100,000.
29-38. (canceled)
39. An electrical energy storage device as in claim 1, wherein the
porous separator material is paper.
40. An electrical energy storage device as in claim 1, wherein the
porous separator material comprises a polymer.
41. An electrical energy storage device as in claim 1, wherein the
porous separator material comprises polypropylene, polyethylene,
cellulose, a polyarylether, or a fluoropolymer.
42-68. (canceled)
69. An electrical energy storage device as in claim 1, wherein the
polymer comprising a substituted or unsubstituted polyacetylene is
provided in a blend with at least one polymer that is different
than the polymer comprising a substituted or unsubstituted
polyacetylene.
70. An electrical energy storage device as in claim 1, wherein the
polymer comprising a substituted or unsubstituted polyacetylene is
provided in a blend with at least one conducting polymer.
71. An electrical energy storage device as in claim 70, wherein the
at least one conducting polymer is a derivative of polyaniline,
polyphenylene, polyarylene, poly(bisthiophene phenylene), a ladder
polymer, poly(arylene vinylene), or poly(arylene ethynyl ene), any
of which is optionally substituted.
72. An electrical energy storage device as in claim 70, wherein the
conducting polymer is an optionally substituted polythiophene or
polymer containing thiophene units that are connected by aromatic
groups or alkenes.
73. An electrical energy storage device as in claim 70, wherein the
conducting polymer is an optionally substituted polypyrrole or
polymer containing pyrrole units that are connected by aromatic
groups or alkenes.
74-128. (canceled)
Description
RELATED APPLICATIONS
[0001] This application claims the benefit under 35 U.S.C. .sctn.
120 of U.S. application Ser. No. 13/799,152, entitled "DEVICES AND
METHODS INCLUDING POLYACETYLENES" filed on Mar. 13, 2013, which is
herein incorporated by reference in its entirety. Application Ser.
No. 13/799,152 claims priority under 35 U.S.C. .sctn. 119(e) to
U.S. Provisional Application Ser. No. 61/623,887, entitled "DEVICES
AND METHODS INCLUDING POLYACETYLENES" filed on Apr. 13, 2012, which
is herein incorporated by reference in its entirety.
FIELD OF THE INVENTION
[0002] Devices for storage of electrical energy are described, as
well as related methods.
BACKGROUND OF THE INVENTION
[0003] Supercapacitors, or electrochemical double-layer capacitors,
have been shown to achieve higher power and longer cycles than
other energy storage devices including batteries. Supercapacitors
have the potential to be useful in a wide range of applications
including automobiles (e.g., hybrid cars), electronics, and other
applications requiring a power source. However, their widespread
use has been limited due to the use of expensive materials and
complex handling procedures in manufacturing.
SUMMARY OF THE INVENTION
[0004] Electrical energy storage device are provided, as well as
related methods. In some embodiments, the electrical energy storage
device comprises a first electrode comprising a polymer comprising
a substituted or unsubstituted polyacetylene; a second electrode in
electrochemical communication with the first electrode; a porous
separator material arranged between the first and second
electrodes; and an electrolyte in electrochemical communication
with the first and second electrodes.
[0005] Methods for fabricating an electrical energy storage device
are also provided. The method may comprise forming a conductive
material comprising a polymer comprising a substituted or
unsubstituted polyacetylene on the surface of a substrate.
[0006] Methods for storing electrical energy are also provided. The
method may comprise applying an electric field to a device
comprising a polymer comprising a substituted or unsubstituted
polyacetylene.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] FIG. 1A shows a schematic representation of an energy
storage device.
[0008] FIG. 1B shows another schematic representation of an energy
storage device.
[0009] FIG. 2 shows the chemical structure of an exemplary
unsubstituted polyacetylene.
[0010] FIG. 3 shows a graph of the voltage of a device including
polyacetylene at various charging states.
[0011] FIG. 4 shows a graph of the estimated capacitance of a
device including polyacetylene on the first discharging curve.
[0012] FIG. 5 shows a graph of the integrated energy input and
output during charging/discharging of a device including
polyacetylene.
[0013] FIG. 6 shows a schematic representation of a single-cell
supercapacitor with polyacetylene as a positive electrode.
[0014] FIG. 7 shows a schematic representation of a multi-cell
supercapacitor with three cells connected in parallel (e.g., a
triple stack) with polyacetylene as a positive electrode.
[0015] Other aspects, embodiments and features of the invention
will become apparent from the following detailed description when
considered in conjunction with the accompanying drawings. The
accompanying figures are schematic and are not intended to be drawn
to scale. For purposes of clarity, not every component is labeled
in every figure, nor is every component of each embodiment of the
invention shown where illustration is not necessary to allow those
of ordinary skill in the art to understand the invention. All
patent applications and patents incorporated herein by reference
are incorporated by reference in their entirety. In case of
conflict, the present specification, including definitions, will
control.
DETAILED DESCRIPTION
[0016] Embodiments described herein relate to compositions,
devices, and methods for storage of energy (e.g., electrical
energy). In some cases, devices including relatively inexpensive
and readily available conductive materials such as
polyacetylene-containing polymers are described.
[0017] In some embodiments, devices for energy storage are
provided. For example, the device may be an electrochemical
double-layer capacitor, also known as a supercapacitor,
supercondenser, electrochemical double-layer capacitor, or
ultracapacitor. Typically, the device may store energy (e.g.,
electric energy) in an electric field that is established by charge
separation at an interface between two electroactive materials
(e.g., electrode and electrolyte). A general embodiment of an
energy storage device can include a first electrode, a second
electrode in electrochemical communication with the first
electrode, and a separator material (e.g., a porous separator
material) arranged between the first and second electrodes. In some
embodiments, the first electrode is a cathode and the second
electrode is an anode. In some embodiments, the first electrode is
an anode and the second electrode is a cathode. The device includes
an electrolyte or other mobile phase that can dissociate into
anions and cations in contact with both electrodes. The components
of the device may be assembled such that the electrolyte is
arranged between the first and second electrodes.
[0018] FIG. 1A shows an illustrative embodiment of a device as
described herein. In the embodiment shown, single-cell device 10
includes a first electrode 20, which includes a conductive material
22 in contact with a substrate 24. A separator material 40 can be
formed adjacent to electrode 20. A second electrode 30 may be
arranged in electrochemical communication with the first electrode.
For example, as shown in FIG. 1, electrode 30 includes a conductive
material 32 in contact with a substrate 34, conductive material 32
being in contact with a surface of separator material 40 that is
opposed to the surface of the separator material that is in contact
with conductive material 22. An electrolyte may be arranged in
contact with both electrode 20 and electrode 30.
[0019] In some cases, the device may be a single-cell device. That
is, the device may include two conductive materials, each formed on
different substrates and each conductive material arranged on an
opposing side of a separator material, as shown in FIGS. 1A-B. In
some cases, the device may be a multi-cell device, for example, as
shown in FIG. 7. It should be understood that there are other
embodiments in which the number and orientation of the components
is varied. In some embodiments, one or more of the device
components can be formed as thin films.
[0020] In one embodiment, the first and second electrodes may be
placed on opposite surfaces of a substantially planar separator
material wherein the thickness of the separator material determines
the distance between the electrodes.
[0021] Some embodiments described herein involve the use of a
polymer comprising a substituted or unsubstituted polyacetylene, as
described more fully below. In some cases, the polymer may have a
substituted or unsubstituted polyacetylene backbone. In some cases,
the polymer may be a copolymer (e.g., random copolymer, block
copolymer, etc.), a portion of which may have a substituted or
unsubstituted polyacetylene backbone. In some cases, the
substituted or unsubstituted polyacetylene polymer may be arranged
in a device as an n-type material within a device. The term "n-type
material" is given its ordinary meaning in the art and refers to a
material that has more negative carriers (electrons) than positive
carriers (holes). In some cases, the substituted or unsubstituted
polyacetylene polymer may be arranged in a device as a p-type
material within a device. The term "p-type material" is given its
ordinary meaning in the art and refers to a material that has more
positive carriers (holes) than negative carriers (electrons). Those
of ordinary skill in the art would be capable of selecting the
particular polyacetylene polymer suitable for use in a particular
application. In some embodiments, the polyacetylene polymer may be
selected to include various electron-withdrawing groups. Examples
of electron-withdrawing groups include, but are not limited to,
fluoro, nitro, cyano, carbonyl groups, sulfonyl, haloaryl (e.g.,
fluorinated aryls), and haloalkyl (e.g., fluorinated alkyls). In
some embodiments, the polyacetylene polymer may be selected to
include various electron-donating groups. Examples of
electron-donating groups include, but are not limited to, alkyl,
amino, methoxy, and the like.
[0022] In some cases, the first electrode includes the polymer
comprising the substituted or unsubstituted polyacetylene. In some
cases, the second electrode includes the polymer comprising the
substituted or unsubstituted polyacetylene. In some cases, both the
first and second electrodes include polymers comprising substituted
or unsubstituted polyacetylenes. In some cases, the polymer may be
a polyacetylene polymer substituted with carbon monoxide groups.
The polymer may, in some cases, be arranged as a component of a
composite material. For example, the composite material may include
the polymer comprising the substituted or unsubstituted
polyacetylene in combination with other components, such as carbon
nanotubes, activated carbon, or a metal oxide. In some embodiments,
the first electrode includes a polymer comprising a substituted or
unsubstituted polyacetylene. In some cases, the first electrode may
include a composite material including the polyacetylene-containing
polymer. The first electrode may include additional components,
such as a charge collector material in physical contact with the
polymer. For example, the polymer may be formed on the surface of a
substrate comprising the charge collector material, i.e., the
polymer may be formed on a conducting plate substrate. The charge
collector material may be any material capable of facilitating the
separation of charge within a double-layer capacitor. In some
cases, the charge collector material includes a metal and/or a
carbon-based material. Examples of charge collector materials
include aluminum, polyacetylene, and glassy carbon.
[0023] In some embodiments, the second electrode may include a
conductive material, including a carbon-based material or a
conducting polymer. For example, the second electrode may include
carbon, activated carbon, graphite, graphene, carbon nanotubes,
and/or a conducting polymer such as polythiophene, polypyrrole, and
the like. In some cases, the second electrode includes a polymer
comprising a substituted or unsubstituted polyacetylene as the
conductive material, or in addition to the conductive material. In
some cases, the second electrode may include a composite material
including the polyacetylene-containing polymer. The second
electrode may include additional components, such as a charge
collector material in physical contact with the conductive
material. For example, the conductive material may be formed on the
surface of a substrate comprising the charge collector material. In
some cases, the charge collector material includes a metal, and/or
a carbon-based material. Examples of charge collector materials
include aluminum, polyacetylene, and glassy carbon.
[0024] Electrodes described herein, including electrodes which
comprise polyacetylene-containing polymers, may include additional
components that may improve the performance, stability and/or other
properties of the polyacetylene-containing polymer or electrode.
For example, the electrode may include a conductive material in
powder form, and may further include a material that binds the
powder particles together. Examples of other additives or modifiers
include metal salts, metal oxides, polydimethylsiloxane,
polystyrene, polypropylene, silicone oil, mineral oil, paraffin, a
cellulosic polymer, polybutadiene, polyneopropene, natural rubber,
polyimide, or other polymers.
[0025] In some cases, at least a portion of an electrode may be
fabricated from a mixture containing the polymer comprising the
substituted or unsubstituted polyacetylene and a fluid carrier. For
example, the mixture may be used to form a film or layer containing
the substituted or unsubstituted polyacetylene via a casting
method, or other methods. The film or layer may be used as part of
an active layer within an electrode. In some cases, the film or
layer may be used as an active layer in the first electrode. In
some cases, the film or layer may be used as an active layer in the
second electrode. In some cases, the films or layers may have a
thickness in the range of about 0.001 mm to about 100 mm, 0.01 mm
to about 100 mm, 0.01 mm to about 10 mm, or, in some cases, about
0.01 mm to about 1 mm.
[0026] In some cases, the polyacetylene-containing polymer may be
combined with one or more polymers having a different chemical
structure, molecular weight, polymer length, polymer morphology,
and/or other polymer characteristic relative to the
polyacetylene-containing polymer. For example, a polymer blend
which includes the polyacetylene-containing polymer may be utilized
in devices described herein. In some cases, the
polyacetylene-containing polymer may be combined with a conducting
polymer. For example, the conducting polymer may be a derivative of
polyaniline, polyphenylene, polyarylene, poly(bisthiophene
phenylene), a ladder polymer, poly(arylene vinylene), or
poly(arylene ethynylene), any of which is optionally substituted.
In some embodiments, the conducting polymer is an optionally
substituted polythiophene or a copolymer thereof with other
conjugated aromatic or alkene units. In some embodiments, the
conducting polymer is an optionally substituted polypyrrole or a
copolymer thereof with other conjugated aromatic or alkene
units.
[0027] The separator material (e.g., porous separator material) may
be any material capable of physically separating the first and
second electrodes, while also allowing fluids and/or charged
species (e.g., electrolyte) to travel from one electrode to
another. The separator material may also be selected to be
chemically inert to other components of the device, so as to not
interfere with device performance (e.g., charge/discharge of the
device). In some cases, the separator material is paper. In some
cases, the separator material comprises a polymer. For example, the
polymer may include polypropylene, polyethylene, cellulose, a
polyarylether, or a fluoropolymer. In some cases, the separator
material is a porous separator material.
[0028] Any component of the device, or portion thereof, may be
porous or may have a sufficient number of pores or interstices such
that the component, or portion thereof, is readily crossed or
permeated by, for example, a fluid. In some cases, a porous
material may improve the performance of the device by
advantageously facilitating the diffusion of charged species to
electroactive portions of the device. In some cases, a porous
material may improve the performance of the device by increasing
the surface area of an electroactive portion of the device. In some
embodiments, a portion of an electrode may be modified to be
porous. In some embodiments, at least a portion of the separator
material may be selected to be porous.
[0029] The device may further include an electrolyte arranged to be
in electrochemical communication with the first and second
electrodes. The electrolyte can be any material capable of
transporting either positively or negatively charged ions or both
between two electrodes and should be chemically compatible with the
electrodes. In some cases, the electrolyte is selected to be
capable of supporting high charge stabilization. In some
embodiments, the electrolyte comprises a liquid. In one set of
embodiment, the electrolyte is an ionic liquid. Other examples of
electrolytes include ethylene carbonate solutions or propylene
carbonate solutions, either of which include at least one salt
having the formula, [(R).sub.4N.sup.+][X.sup.-], wherein X is
(PF.sub.6).sup.-, (BF.sub.4).sup.-, (SO.sub.3R.sup.a).sup.-,
(R.sup.aSO.sub.2--N--SO.sub.2R.sup.a).sup.-, CF.sub.3COO.sup.-,
(CF.sub.3).sub.3CO.sup.- or (CF.sub.3).sub.2CHO).sup.-, wherein R
is alkyl and R.sup.a is alkyl, aryl, fluorinated alkyl, or
fluorinated aryl. In some embodiments the nitrogen of the ammonium
ion may be part of a ring system. In another embodiment, the
electrolyte may include a quaternary nitrogen species in which the
nitrogen has an sp.sup.2 electronic configuration, such as an
imidazolium cation.
[0030] In some embodiments, the electrolyte may selected to be
substantially free of metal-containing species (e.g., metals or
metal ions), or may include less than about 1%, less than about
0.1%, less than about 0.01%, less than about 0.001%, or less than
about 0.0001% of metals and/or metal ions, based on the total
amount of electrolyte. In some embodiments, the electrolyte may be
selected to be substantially free of lithium-containing species or
lithium ion-containing species. In some embodiments, the
electrolyte does not include metal-containing species.
[0031] Methods for storing electrical energy using any of the
devices described herein are also provided. For example, the method
may involve application of an electric field to a device as
described herein. In some embodiments, the device may exhibit a
specific capacitance of about 50 Farad/g, about 100 Farad/g, about
150 Farad/g, about 200 Farad/g (e.g., about 220 Farad/g), about 300
Farad/g. about 400 Farad/g, or, in some cases, about 500 Farad/g.
For example, the device may exhibit a specific capacitance in the
range of about 50 Farad/g to about 500 Farad/g. about 100 Farad/g
to about 500 Farad/g, about 200 Farad/g to about 500 Farad/g, about
300 Farad/g to about 500 Farad/g, or about 400 Farad/g to about 500
Farad/g.
[0032] In some embodiments, the device may store about 50 kJ/kg,
about 100 kJ/kg, about 200 kJ/kg, about 300 kJ/kg, about 400 kJ/kg,
about 500 kJ/kg, about 600 kJ/kg, of electrical energy. In some
cases, the device may store between about 50 kJ/kg and about 600
kJ/kg of electrical energy.
[0033] In some cases, the device is charged to about 1.5 V, about
2.0 V, about 2.5 V (e.g., about 2.7 V), about 3.0 V, or, about 3.5
V.
[0034] Devices and methods disclosed herein may capable of achieve
relatively high specific energy density. In some embodiments, the
device may achieve specific energy densities beyond those which are
produced by devices limited by thermodynamic reduction/oxidation
potentials, such as batteries (e.g., lithium-containing or lithium
ion-containing batteries). Devices and methods disclosed herein can
supply individual cell voltages that exceed the thermodynamic
limits that would result in batteries made from the similar
materials. In some embodiments, the device has a specific energy
density of about 100 kJ/kg, about 200 kJ/kg, about 300 kJ/kg, about
400 kJ/kg, about 500 kJ/kg, or about 600 kJ/kg, based on the total
weight of conductive material and, if present,
polyacetylene-containing materials within the electrodes. For
example, in embodiments where an electrode includes a composite
material comprising a polymer comprising a substituted or
unsubstituted polyacetylene and a conductive material, the specific
energy density is based on the total weight of the conductive
material and the polymer comprising the substituted or
unsubstituted polyacetylene.
[0035] At least some of the devices disclosed herein provide an
energy storage mechanism that includes both (1) electrostatic
storage of electrical energy achieved by separation of charge in a
Helmholtz double layer at the surface of a conductor electrode and
an electrolytic solution electrolyte; and (2) electrochemical
storage of electrical energy achieved by redox reactions on the
surface of at least one of the electrodes or by specifically
adsorbed ions that results in a reversible Faradaic charge-transfer
on the electrode.
[0036] Methods for fabricating the devices described herein are
also provided. The method may involve forming a conductive material
that includes a polymer comprising a substituted or unsubstituted
polyacetylene on the surface of a substrate, such as a charge
collector substrate (e.g., conducting plate). The method may
further involve arranging a separator material in contact with the
conductive material. For example, a device may be fabricated by
forming a first conductive material including a
polyacetylene-containing polymer the surface of a first substrate,
and arranging a first surface of a separator material in contact
with the first conductive material. A second, conductive material
may then be arranged in contact with a second, opposing side of the
separator material, such that the first conductive material is in
electrochemical communication with the second conductive material.
The separator material may also be arranged to physically separate
the first and second conductive materials. The method may further
involve arranging an electrolyte in contact with the first and
second electrodes. FIGS. 1A-B show illustrative embodiments of
devices as described herein.
[0037] Conductive materials described herein may be formed on a
substrate using various methods, including evaporation, direct
polymerization, inkjet printing, casting methods including
drop-casting and spin-casting, and the like. In some cases, the
conductive material is in the form of a solid, which is then
arranged/assembled on a substrate. For example, the conductive
material (e.g., polyacetylene-containing polymer) may be in the
form of a powder and arranged between the substrate and another
device component (e.g., the porous separator material). In other
cases, the conductive material is combined with a fluid carrier or
solvent to form a solution, dispersion, or suspension, and the
conductive material is formed on the substrate via a casting method
(e.g., spin-casting, drop-casting, etc.) or by printing (e.g.,
inkjet printing). For example, a mixture comprising the polymer
comprising the substituted or unsubstituted polyacetylene and a
fluid carrier may be provided and then formed into a film. In some
cases, films having a thickness in the range of about 0.01 mm to
about 1 mm may be formed using such methods. In other cases, the
polyacetylene-containing polymer is directly synthesized on the
substrate. The conductive material may be treated by various
methods to improve processability, physical and/or mechanical
stability, and/or device performance. In some cases, the conductive
material may be subjected to application of high pressure prior to
formation on a substrate. For example, the conductive material
(e.g., polyacetylene-containing polymer) may be in the form of a
powder, which is then placed into a hydraulic press to form a
pellet, film, or other shape. In some cases, the conductive
material may be subjected to crosslinking conditions and/or solvent
treatments.
[0038] As described herein, the device may include a
polyacetylene-containing polymer. In some cases, the devices
includes a substituted or an unsubstituted polyacetylene. In some
cases, the devices includes a copolymer comprising polyacetylene.
The polymer backbone may include cis double bonds, trans double
bonds, or combinations thereof. In some embodiments, the polymer
may include the structure,
##STR00001##
[0039] wherein:
[0040] R.sup.1, R.sup.2, R.sup.3, and R.sup.4 can be the same or
different and each is H, alkyl, heteroalkyl, aryl, heteroaryl,
heterocyclyl, halo, cyano, sulfonyl, sulfate, phosphonyl,
phosphate, or carbonyl group (e.g., carboxylate, ketones such as
alkylcarbonyl or arylcarbonyl, etc.), any of which is optionally
substituted; and
[0041] m and n are each greater than 1.
[0042] In some embodiments. R.sup.1, R.sup.2, R.sup.3, and R.sup.4
are each H. In some embodiments, at least one of R.sup.1, R.sup.2,
R.sup.3, and R.sup.4 is halo (e.g., fluorine).
[0043] In some embodiments, the polymer has the structure,
##STR00002##
[0044] wherein m and n are greater than 1.
[0045] In some embodiments, the polymer has the structure,
##STR00003##
[0046] wherein:
[0047] R.sup.1, R.sup.2, R.sup.3, and R.sup.4 can be the same or
different and each is H, alkyl, aryl, halo, cyano, sulfonyl,
sulfate, phosphonyl, phosphate, or carbonyl group (e.g.,
carboxylate, ketones such as alkylcarbonyl or arylcarbonyl, etc.),
any of which is optionally substituted; and
[0048] m, m', n, and n' are each greater than 1.
[0049] In some embodiments, the polymer has the structure,
##STR00004##
[0050] wherein:
[0051] R.sup.1, R.sup.2, R.sup.3, and R.sup.4 can be the same or
different and each is H, alkyl, aryl, halo, cyano, sulfonyl,
sulfate, phosphonyl, phosphate, or carbonyl group (e.g.,
carboxylate, ketones such as alkylcarbonyl or arylcarbonyl, etc.),
any of which is optionally substituted; and
[0052] m, m', n, n', and o are each greater than 1.
[0053] In any of the embodiments disclosed herein, n, n', m, m' and
o are the same or different and are an integer between 2 and
10,000, or between 10 and 10,000, or between 100 and 10,000, or
between 100 and 1.000. The molecular weight of the
polyacetylene-containing polymer may be between about 500 and about
1,000.000, or between about 500 and about 100,000, or between about
10,000 and about 100,000, or the like.
[0054] Methods described herein may involve the synthesis of
polymers including a substituted or unsubstituted polyacetylene. In
some cases, the polymers may be synthesized in the presence of a
fluid carrier, such as toluene. For example, the polymer may be
produced using cationic methods, metal catalyzed insertion
reactions, or metal alkylidene reactions proceeding through
metallocyclobutene intermediates (also known as a ring opening
metathesis polymerization if the acetylene is considered to be a
two-membered cyclic alkene), and the like. Typically, monomeric
species, or a combination of monomeric species, are exposed to a
catalyst or catalyst mixture under appropriate conditions in a
reaction vessel to produce the polymer. In some cases, the
monomeric species includes a carbon-carbon triple bond. In some
cases, the monomeric species includes a carbon-carbon double bond.
In some cases, the monomeric species includes a carbonyl or C.dbd.O
group. The monomeric species may be in vapor phase or in solution
phase, and may optionally be combined with a fluid carrier or
solvent (e.g., organic solvent) in the reaction vessel. In an
illustrative embodiment, acetylene gas may be introduced to the
reaction vessel containing a catalyst or catalyst mixture. In some
cases, the polymer may be synthesized in a gel form. i.e., swollen
with solvent and/or other additives. In some cases, the polymer
(e.g., polyacetylene) may be synthesized directly onto a substrate,
e.g., as a film.
[0055] In some cases, the method involves polymerizing at least one
monomeric species including a carbon-carbon triple bond to form a
polyacetylene-containing polymer. The carbon-carbon triple bond may
be unsubstituted (e.g., acetylene) or substituted with one or more
substituents. In some cases, the monomeric species may be
polymerized in the presence of additional monomers (e.g., to form a
copolymer). Examples of additional monomeric species include carbon
monoxide, carbon disulfide, and the like. In one set of
embodiments, a monomeric species including a carbon-carbon triple
bond and carbon monoxide are copolymerized to form a polymer
including alpha, beta-unsaturated carbonyl moieties.
[0056] Those of ordinary skill in the art would be able to select a
catalyst or catalyst mixture suitable for use in the synthesis of
polymers described herein. The catalyst may be in solid form (e.g.,
particles), or combined with a solvent to forma solution,
suspension, or dispersion. In some cases, the catalyst is a
metal-containing catalyst or catalyst mixture. For example, the
catalyst or catalyst mixture may include aluminum, titanium,
tungsten, ruthenium, rhodium, molybdenum, or combinations thereof.
In some cases, the catalyst may be a mixture including titanium and
aluminum (e.g., Ziegler-Natta catalyst). In some embodiments, the
catalyst or catalyst mixture may comprise ruthenium, rhodium,
tungsten, or molybdenum. Examples of catalyst and catalyst mixtures
include, but are not limited to, the Ziegler-Natta catalyst (e.g.,
prepare from,
benzylidene-bis(tricyclohexylphosphine)dichloro-ruthenium (Grubbs'
first generation catalyst),
benzylidene[1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro-
-(tricyclohexylphosphine)ruthenium (Grubbs' second generation
catalyst), and Schrock catalysts (e.g.,
tris(t-butoxy)(2,2-dimethylpropylidyne)(VI)tungsten).
[0057] In some cases, the catalyst or catalyst mixture is in the
form of particles. For example, the particles may be
aerosol-generated catalyst particles.
[0058] In some cases, polymers as described here may be produced as
highly crystalline polymers. In some cases, the polymers may forma
solid state structure that is substantially fixed.
[0059] The polymerization step may be performed in the presence of
additional components. For example, monomeric species may be
polymerized in the presence of an additive, such that the additive
is entrapped or dispersed throughout the resulting polymer
material. Such additives may be selected to be electroactive
materials (e.g., polymers) that can enhance performance of the
device, e.g., enhance charging, discharging, and/or stabilization
of a charged state.
[0060] In some cases, the additive may be a passive material that
can be removed post-polymerization. For example, monomeric species
may be polymerized in the presence of an additive, wherein at least
some of the additive is removed post-polymerization to produce a
porous polymer material. In some cases, the additive may be removed
by treatment with heat. In some cases, the additive may be removed
by treatment with a solvent.
[0061] For example, the polymerization may be performed in the
presence of a phase-separating polymer that can be removed after
polymerization to yield a porous material. Without wishing to be
bound by any theory, since the capacitance of the device may be
proportional to the surface area of the interface between an
electrode and electrolyte, increasing the surface area of the
interface can increase the amount of energy stored in the
device.
[0062] Other examples of additives that may be used during
polymerization include other polymers and/or modifiers, such as
polydimethylsiloxane, polystyrene, polyethylene, polypropylene,
silicone oil, mineral oil, paraffin, cellulosic polymers,
polybutadiene, polyneopropene, natural rubber, or polyimide.
[0063] Those of ordinary skill in the art would be able to select a
set of conditions appropriate for a particular polymerization
reaction. For example, the conditions may be selected based on the
chemical structure(s) of the monomeric species (e.g., selection of
catalyst, solvents, etc.), the stability of the catalyst in the
presence of air and/or water, and/or the compatibility (e.g.,
solubility) of various reaction components with one another.
Exemplary methods for synthesizing polymers which include a
substituted or unsubstituted polyacetylene are described in, for
example, Liu et al., "Acetylenic Polymers: Syntheses, Structure,
and Functions," Chem. Rev. 2009, 109, 5799; MacInnes et al.,
"Organic Batteries: Reversible n- and p-Type Electrochemical Doping
of Polyacetylene. (CH).sub.x." J.C.S. Chem. Comm. 1981, 371; and
Ito et al., "Simultaneous Polymerization and Formation of
Polyacetylene Film on the Surface of Concentrated Soluble
Ziegler-Type Catalyst Solution," J. Polymer Science 1974, 12, 11,
the contents of which documents are incorporated herein by
reference in their entirety for all purposes.
[0064] The polyacetylene-containing polymer may be treated before
and/or after fabrication of the electrodes, or prior to, during, or
after the polymerization step, to improve the performance,
stability, and/or other property of the device. In some cases, the
polymer may be treated to enhance the charge storage ability of the
device. In some cases, the polymer may be treated to stabilize the
polymer material. Such treatments may include treatment with
dichloroketene (Cl.sub.2C.dbd.C.dbd.O), aromatic diazonium salts
(Ar--N.sup.2+), disulfides (R--S--S--R), organic sulfur chlorides
(RS--Cl), sulfur chlorides (SCl.sub.2 and S.sub.2Cl.sub.2), metal
salts and oxides including MnO.sub.2 or Mn(OAc).sub.2, silicon
hydrides (e.g., R.sub.nSH.sub.4 where R can be alkyl, aryl, vinyl,
alkoxy, phenoxy, carboxylate and n=0-4) and disilanes, compounds
having one or more silicon hydride group (e.g., SiH) including
oligomers and cyclic compounds, polymers containing silicon
hydrides such as copolymers with polydimethylsiloxane, phenols
including sterically hindered phenols (e.g., butylated hydroxyl
toluene (BHT) and derivatives thereof), and other radical
scavengers. For example, the polymerization step may be performed
in the presence of a stabilizing agent, such that that stabilizing
agent is dispersed throughout the resulting polymer material.
[0065] Methods described herein may allow for simplified methods
for manufacturing materials and devices including
polyacetylene-containing polymers. In some embodiments, a
continuous method for the formation of the polyacetylene-containing
particles, films, or other materials may be provided. The
continuous process may involve polymerization of a monomer
dissolved in a condensed phase (e.g., solution phase) or direct
polymerization of a vapor-phase monomer.
[0066] For example, the method may involve continuously moving a
plurality of substrates through various reaction zones to form a
polyacetylene-containing material. In some cases, a substrate may
be passed through a first reaction zone, wherein a catalyst
material (e.g., catalyst particles) may be formed on the substrate.
The substrate containing the catalyst material may then pass
through a second reaction zone containing a monomeric species
(e.g., acetylene gas), wherein polymerization takes place at the
surface of the substrate on the catalyst material. Such methods may
allow for the production of large quantities of
polyacetylene-containing materials and/or formation of
polyacetylene-containing materials on relatively large surface
areas.
[0067] The substrate can be any material capable of supporting an
electrode and electrolyte, as described herein. The substrate may
be selected to have a thermal coefficient of expansion similar to
those of the other components of the device to promote adhesion and
prevent separation of the components at various temperatures. In
some cases, the substrate may include materials capable of
facilitating the separation of charge within, for example, a
double-layer capacitor, i.e., the substrate may function as a
charge collector. Examples of substrates include metal (e.g.,
aluminum) or metal-containing substrates, polymer substrates, and
carbon-based (e.g., carbon, glassy carbon, activated carbon,
graphene, graphite, carbon nanotubes, etc.) substrates. The
dimensions of the substrate may be any length, width, and thickness
that is desired for a particular end use and may be square,
rectangular, circular, or otherwise shaped.
[0068] Various fluid carriers or solvents may be suitable for use
in embodiments described herein. In some cases, the fluid carrier
may be an organic solvent. In some cases, the fluid carrier may be
an aqueous solvent. Examples of fluid carriers and solvents
include, but are not limited to, water, chloroform, carbon dioxide,
toluene, benzene, hexane, dichloromethane, tetrahydrofuran,
ethanol, acetone, or acetonitrile.
[0069] The term "polymers," as used herein, is given its ordinary
meaning in the art and refers to extended molecular structures
comprising a backbone (e.g., non-conjugated backbone, conjugated
backbone) which optionally contain pendant side groups, where
"backbone" refers to the longest continuous bond pathway of the
polymer. Polymers may also include oligomers. In some embodiments,
the polymer comprises a non-conjugated polymer backbone. In some
embodiments, at least a portion of the polymer is conjugated, i.e.
the polymer has at least one portion along which electron density
or electronic charge can be conducted, where the electronic charge
is referred to as being "delocalized." In some cases, the polymer
is a pi-conjugated polymer, where p-orbitals participating in
conjugation can have sufficient overlap with adjacent conjugated
p-orbitals. In some cases, the polymer is a sigma-conjugated
polymer. In one embodiment, at least a portion of the backbone is
conjugated. In one embodiment, the entire backbone is conjugated
and the polymer is referred to as a "conjugated polymer." Polymers
having a conjugated pi-backbone capable of conducting electronic
charge may also be referred to as "conducting polymers." In some
cases, the conjugated pi-backbone may be defined by a plane of
atoms directly participating in the conjugation, wherein the plane
arises from a preferred arrangement of the p-orbitals to maximize
p-orbital overlap, thus maximizing conjugation and electronic
conduction.
[0070] As used herein, the term "alkyl" refers to the radical of
saturated aliphatic groups, including straight-chain alkyl groups,
branched-chain alkyl groups, cycloalkyl (alicyclic) groups, alkyl
substituted cycloalkyl groups, and cycloalkyl substituted alkyl
groups. In some embodiments, a straight chain or branched chain
alkyl may have 30 or fewer carbon atoms in its backbone, and, in
some cases, 20 or fewer. In some embodiments, a straight chain or
branched chain alkyl has 12 or fewer carbon atoms in its backbone
(e.g., C.sub.1-C.sub.12 for straight chain, C.sub.3-C.sub.12 for
branched chain), or, in some cases, 6 or fewer, or 4 or fewer.
Likewise, some cycloalkyls have from 3-10 carbon atoms in their
ring structure, or have 5, 6 or 7 carbons in the ring structure.
Examples of alkyl groups include, but are not limited to, methyl,
ethyl, propyl, isopropyl, cyclopropyl, butyl, isobutyl, tert-butyl,
cyclobutyl, hexyl, cyclohexyl, and the like.
[0071] The term "heteroalkyl" refers to an alkyl group as described
herein in which one or more carbon atoms is replaced by a
heteroatom. Suitable heteroatoms include oxygen, sulfur, nitrogen,
phosphorus, and the like. Examples of heteroalkyl groups include,
but are not limited to, alkoxy, amino, thioester, and the like.
[0072] The term "aryl" refers to aromatic carbocyclic groups,
optionally substituted, having a single ring (e.g., phenyl),
multiple rings (e.g., biphenyl), or multiple fused rings in which
at least one is aromatic (e.g., 1,2,3,4-tetrahydronaphthyl,
naphthyl, anthryl, or phenanthryl). That is, at least one ring may
have a conjugated pi electron system, while other, adjoining rings
can be cycloalkyls, cycloalkenyls, cycloalkynyls, aryls and/or
heterocyclyls. The aryl group may be optionally substituted, as
described herein. "Carbocyclic aryl groups" refer to aryl groups
wherein the ring atoms on the aromatic ring are carbon atoms.
Carbocyclic aryl groups include monocyclic carbocyclic aryl groups
and polycyclic or fused compounds (e.g., two or more adjacent ring
atoms are common to two adjoining rings) such as naphthyl
groups.
[0073] The term "heteroaryl" refers to aryl groups comprising at
least one heteroatom as a ring atom.
[0074] The term "heterocyclyl" refers to refer to cyclic groups
containing at least one heteroatom as a ring atom, in some cases, 1
to 3 heteroatoms as ring atoms, with the remainder of the ring
atoms being carbon atoms. Suitable heteroatoms include oxygen,
sulfur, nitrogen, phosphorus, and the like. In some cases, the
heterocycle may be 3- to 10-membered ring structures, or in some
cases 3- to 7-membered rings, whose ring structures include one to
four heteroatoms. The term "heterocycle" may include heteroaryl
groups (e.g., aromatic heterocycles), saturated heterocycles (e.g.,
cycloheteroalkyl) groups, or combinations thereof. The heterocycle
may be a saturated molecule, or may comprise one or more double
bonds. In some case, the heterocycle is an aromatic heterocycle,
such as pyrrole, pyridine, and the like. In some cases, the
heterocycle may be attached to, or fused to, additional rings to
form a polycyclic group. In some cases, the heterocycle may be part
of a macrocycle. The heterocycle may also be fused to a spirocyclic
group. In some cases, the heterocycle may be attached to a compound
via a nitrogen or a carbon atom in the ring.
[0075] Heterocycles include, for example, thiophene,
benzothiophene, thianthrene, furan, tetrahydrofuran, pyran,
isobenzofuran, chromene, xanthene, phenoxathiin, pyrrole,
dihydropyrrole, pyrrolidine, imidazole, pyrazole, pyrazine,
isothiazole, isoxazole, pyridine, pyrazine, pyrimidine, pyridazine,
indolizine, isoindole, indole, indazole, purine, quinolizine,
isoquinoline, quinoline, phthalazine, naphthyridine, quinoxaline,
quinazoline, cinnoline, pteridine, carbazole, carboline, triazole,
tetrazole, oxazole, isoxazole, thiazole, isothiazole,
phenanthridine, acridine, pyrimidine, phenanthroline, phenazine,
phenarsazine, phenothiazine, furazan, phenoxazine, pyrrolidine,
oxolane, thiolane, oxazole, oxazine, piperidine, homopiperidine
(hexamnethyleneimine), piperazine (e.g., N-methyl piperazine),
morpholine, lactones, lactams such as azetidinones and
pyrrolidinones, sultams, sultones, other saturated and/or
unsaturated derivatives thereof, and the like. The heterocyclic
ring can be optionally substituted at one or more positions with
such substituents as described herein. In some cases, the
heterocycle may be bonded to a compound via a heteroatom ring atom
(e.g., nitrogen). In some cases, the heterocycle may be bonded to a
compound via a carbon ring atom. In some cases, the heterocycle is
pyridine, imidazole, pyrazine, pyrimidine, pyridazine, acridine,
acridin-9-amine, bipyridine, naphthyridine, quinoline,
benzoquinoline, benzoisoquinoline, phenanthridine-1,9-diamine, or
the like.
[0076] As used herein, the term "halo" designates --F, --Cl, --Br,
or --I.
[0077] The terms "carboxyl group," "carbonyl group," and "acyl
group" are recognized in the art and can include such moieties as
can be represented by the general formula:
##STR00005##
wherein W is H, OH, O-alkyl, O-alkenyl, or a salt thereof. Where W
is O-alkyl, the formula represents an "ester." Where W is OH, the
formula represents a "carboxylic acid." The term "carboxylate"
refers to an anionic carboxyl group. In general, where the oxygen
atom of the above formula is replaced by sulfur, the formula
represents a "thiolcarbonyl" group. Where W is a S-alkyl, the
formula represents a "thiolester." Where W is SH, the formula
represents a "thiolcarboxylic acid." On the other hand, where W is
alkyl or aryl, the above formula represents a "ketone" group (e.g.,
alkylcarbonyl, arylcarbonyl, etc.). Where W is hydrogen, the above
formula represents an "aldehyde" group.
[0078] Any of the above groups may be optionally substituted. As
used herein, the term "substituted" is contemplated to include all
permissible substituents of organic compounds, "permissible" being
in the context of the chemical rules of valence known to those of
ordinary skill in the art. It will be understood that "substituted"
also includes that the substitution results in a stable compound,
e.g., which does not spontaneously undergo transformation such as
by rearrangement, cyclization, elimination, etc. In some cases,
"substituted" may generally refer to replacement of a hydrogen with
a substituent as described herein. However, "substituted," as used
herein, does not encompass replacement and/or alteration of a key
functional group by which a molecule is identified, e.g., such that
the "substituted" functional group becomes, through substitution, a
different functional group. For example, a "substituted phenyl
group" must still comprise the phenyl moiety and cannot be modified
by substitution, in this definition, to become, e.g., a pyridine
ring. In a broad aspect, the permissible substituents include
acyclic and cyclic, branched and unbranched, carbocyclic and
heterocyclic, aromatic and nonaromatic substituents of organic
compounds. Illustrative substituents include, for example, those
described herein. The permissible substituents can be one or more
and the same or different for appropriate organic compounds. For
purposes of this invention, the heteroatoms such as nitrogen may
have hydrogen substituents and/or any permissible substituents of
organic compounds described herein which satisfy the valencies of
the heteroatoms.
[0079] Examples of substituents include, but are not limited to,
halogen, azide, alkyl, aralkyl, alkenyl, alkynyl, cycloalkyl,
hydroxyl, alkoxyl, amino, nitro, sulfhydryl, imino, amido,
phosphonate, phosphinate, carbonyl, carboxyl, silyl, ether,
alkylthio, sulfonyl, sulfonamido, ketone, aldehyde, ester,
heterocyclyl, aromatic or heteroaromatic moieties. --CF.sub.3,
--CN, aryl, aryloxy, perhaloalkoxy, aralkoxy, heteroaryl,
heteroaryloxy, heteroarylalkyl, heteroaralkoxy, azido, amino,
halide, alkylthio, oxo, acylalkyl, carboxy esters, -carboxamido,
acyloxy, aminoalkyl, alkylaminoaryl, alkylaryl, alkylaminoalkyl,
alkoxyaryl, arylamino, aralkylamino, alkylsulfonyl,
-carboxamidoalkylaryl, -carboxamidoaryl, hydroxyalkyl, haloalkyl,
alkylaminoalkylcarboxy-, aminocarboxamidoalkyl-, cyano,
alkoxyalkyl, perhaloalkyl, arylalkyloxyalkyl, and the like.
EXAMPLES AND EMBODIMENTS
Example 1
[0080] The following example describes the preparation of a
polyacetylene polymer. To a 100 mL Schlenk flask purged with dry
nitrogen was added dry toluene (30 mL), followed by
tetrabutoxytitanium (5.2 g, 15 mmol). Triethylaluminum solution in
toluene (31 mL, 1.9 M, 60 mmoL) was slowly added, and the resulting
mixture was stirred for 4 h at room temperature to form the
catalyst solution, which was stored under nitrogen.
[0081] In a separate flask was added dry toluene (40 mL) and small
amount of the catalyst solution (0.6 mL). Acetylene gas, which was
purified by passing through a dry ice trap, was introduced via a
syringe needle. The polymerization was allowed to continue for 16
h. The polymer was suspended in isopropanol, and the precipitates
were collected by filtration, washed with isopropanol, and dried
under vacuum to yield polyacetylene (3.4 g).
Example 2
[0082] In the following example, a supercapacitor device was
assembled according to FIG. 1B. The negative electrode was
Spectracarb Activated Carbon Fabric Type 2225 from Engineered
Fibers Technology, LLC. In a representative experiment,
polyacetylene (5.9 mg) was ground into fine particles and evenly
spread on the surface of half of the 2.5.times.2.5 cm.sup.2 glassy
carbon, and the polyacetylene was then completely covered with a
piece of filter paper (Whatman #6). On top of the filter paper was
placed the carbon cloth cut into rectangular shape, just enough to
cover the polyacetylene area (the weight of the carbon cloth was 50
mg). On top of the carbon cloth was placed another 2.5.times.2.5
cm.sup.2 glassy carbon square. The completed assembly was then
clamped together with bind clips, and electrolyte (prepared by
mixing tetraethyammonium hexafluorophosphate, propylene carbonate,
and ethylene carbonate in a weight ratio of 2:1:1) was then added
through the edge of the device.
Example 3
[0083] The following example describes the performance of the
supercapacitor device described in Example 2. The device was
analyzed by charging at constant current (0.002 A) until the
voltage reached 2.7 V, and then discharging at constant current
(0.002 A) until the voltage reached 0. The device voltage was
monitored continuously every microsecond during the charging
discharging process. The charging/discharging process was repeated
three times. FIG. 3 shows the voltage charging state relationship
during the first three cycles. The capacitance of the device was
estimated as 1.53 by calculating the reciprocal of the line passing
the both ends of the curve. (FIG. 4) The specific capacitance based
on polyacetylene was calculated to be 259 kF/kg. The specific
energy based on polyacetylene was calculated by integrate the
energy released during the first discharging (FIG. 5, the total
energy released during the first discharging was 5.2 J) and
dividing the total by the mass of the polyacetylene. The calculated
specific energy density was 882 kJ/kg.
Example 4
[0084] In the following example, various electrode materials were
prepared.
[0085] In one exemplary procedure, polyacetylene films were
prepared using a binder such as polytetrafluoroethylene (PTFE). In
a representative procedure, polyacetylene (1 g) was ground into
fine powder and mixed with polytetrafluoroethylene (PTFE, 60%
suspension in water, 0.167 g), and further diluted with water (2
g). The resulting dough-like material was rolled into 200 micron
film on a rolling mill. The resulting film was then dried under
vacuum and cut into desirable sizes to be used as positive
electrodes in supercapacitor devices.
[0086] In another exemplary procedure, polyacetylene films using
hydraulic press, without addition of any binders. In a
representative procedure, polyacetylene (4 g) was ground into fine
powder, and was evenly loaded onto a 5.times.5 cm.sup.2 square
shaped press die. 12 Tons of force was applied to result in a
5.times.5 cm.sup.2 polyacetylene film, which was then cut into
desirable sizes to be used as electrodes in supercapacitor
devices.
[0087] In another exemplary procedure, activated carbon films were
prepared using polytetrafluoroethylene (PTFE) as binder. In a
representative procedure, activated carbon (2.0 g) was mixed with
polytetrafluoroethylene (PTFE, 60% suspension in water, 0.5 g) and
water (4.5 mL). The resulting mixture was kneaded into a dough-like
material and rolled into 200 micron film on a rolling mill. The
film was then cut into desirable sizes to be used as electrodes in
supercapacitor devices.
Example 5
[0088] In the following example, single-cell capacitors were
prepared using polyacetylene films as positive electrodes. The
films were prepared with a polytetrafluoroethylene (PTFE) binder,
according to the procedure described in Example 4.
[0089] A polyacetylene film (168.2 mg), activated carbon film
(213.4 mg), and cellulose separator, all saturated with electrolyte
(I-Ethyl-3-methylimidazolium tetrafluoroborate), were assembled
with aluminum foil as shown in FIG. 6. The interfaces between
aluminum foil/polyacetylene film and aluminum foil/activated carbon
film were dusted with activated carbon powder (6.9 mg and 5.1 mg
respectively) to enhance conductivity. The completed assembly was
then pressed between two glass slides held together by binder
clip.
[0090] The performance of this device was tested by passing a
constant current into polyacetylene film from the activated carbon
film, until the potential difference between the two electrodes
reached 3.5 V, and then the direction of the current was reversed.
The energy density of the completed device based on energy released
during first cycle was 65 kJ/kg (245 kJ/kg based on the total
weight of carbon and polyacetylene materials on the
electrodes).
Example 6
[0091] In the following example, single-cell capacitors were
prepared using pressed polyacetylene films as positive electrodes.
The films were prepared with a polytetrafluoroethylene (PTFE)
binder, according to the procedure described in Example 4. A
polytetrafluoroethylene film, binder (198.0 mg), activated carbon
film (217.5 mg), and cellulose separator, all saturated with
electrolyte (1-ethyl-3-methylimidazolium tetrafluoroborate), were
assembled with aluminum foil according to FIG. 6. The interfaces
between aluminum foil/polyacetylene film and aluminum
foil/activated carbon film were dusted with activated carbon powder
(10.3 mg and 10.2 mg respectively) to enhance conductivity. The
completed assembly was then pressed between two glass slides held
together by binder clip.
[0092] The performance of this device was tested by passing a
constant current into polyacetylene film from the activated carbon
film, until the potential difference between the two electrodes
reached 3.5 V, and then the direction of the current was reversed.
The energy density of the completed device based on energy released
during first cycle was 81 kJ/kg (256 kJ/kg based on the total
weight of carbon and polyacetylene materials on the
electrodes).
Example 7
[0093] In the following example, multi-cell capacitors were
prepared using polyacetylene films as positive electrodes. Three
polyacetylene films (220.2 mg, 227.3 mg, and 216.8 mg), three
activated carbon films (219.9 mg, 249.5 mg, 297.4 mg), and
cellulose separators, all saturated with electrolyte
(1-ethyl-3-methylimidazolium tetrafluoroborate), were assembled
with aluminum foils according to FIG. 7. The interfaces between
aluminum foil/polyacetylene film and aluminum foil/activated carbon
film were dusted with activated carbon powder (9.9-11.2 mg) to
enhance conductivity. The completed assembly was then pressed
between two glass slides held together by binder clip.
[0094] The performance of this device was tested by passing a
constant current into polyacetylene film from the activated carbon
film, until the potential difference between the two electrodes
reached 3.5 V, and then the direction of the current was reversed.
The energy density of the completed device based on energy released
during first cycle was 60 kJ/kg (242 kJ/kg based on the total
weight of carbon and polyacetylene materials on the
electrodes).
[0095] Having thus described several aspects of some embodiments,
it is to be appreciated various alterations, modifications, and
improvements will readily occur to those skilled in the art. Such
alterations, modifications, and improvements are intended to be
part of this disclosure, and are intended to be within the spirit
and scope of the invention. Accordingly, the foregoing description
and drawings are by way of example only.
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